Why We're Mad for Mars

This panorama is a mosaic of images taken by the Mast Camera (Mastcam) on NASA's Mars rover Curiosity while the rover was working at a site called "Rocknest" in October and November 2012.

An excited comment by a NASA scientist set off a bout of feverish online speculation last week about what new discoveries might be coming from the surface of Mars.

John Grotzinger, the principal investigator for NASA's Mars Curiosity rover mission, told an NPR reporter that the rover's soil sampler analysis had turned up something exciting.

"This data is gonna be one for the history books," he said. "It's looking really good."

The comments kicked off immediate online speculation on what the finding could be, but NASA immediately began to manage expectations, with a spokesperson telling CBS News that the discovery was "nothing earthshaking."

But try as it might, NASA likely can't tamp down enthusiasm about the Red Planet. Earth's neighbor has long fascinated the public for its potential to have a history of life, or even to one day support a future human colony.

The lure of Mars

Until the first spacecraft flybys of Mars in the 1960s, scientists believed the planet might have liquid water and sustain life. That possibility was enough to fascinate the public, Bob Crossley, author of "Imagining Mars: A Literary History" (Wesleyan, 2011), told LiveScience in August.

"Somewhere deep in my own psyche, and maybe for other people as well, there is a desire for another world," said Crossley, an emeritus professor of English at the University of Massachusetts. "For me, the deepest meaning of Mars is it represents some kind of longing for something outside ourselves, something outside our own world." [5 Mars Myths and Misconceptions]

Literary greats like Ray Bradbury likely helped boost Mars' profile; you don't have to be a planetary science geek to love "The Martian Chronicles." Nor do you have to love astronomy to enjoy sci-fi films such as "Total Recall," which is set on the planet. This cultural cachet likely increases familiarity with Mars among the public.

Disappointment in Mars

Of course, familiarity can breed contempt. Bill Sheehan, a psychiatrist and author of "Mars: The Lure of the Red Planet" (Prometheus Books, 2001), said NASA's Mariner missions to Mars in the 1960s demoralized the public when they sent back images of a dead, cratered planet.

"The less defined an object is like Mars, the more evocative it is. We use it as a Rorschach to project our hopes and fears on to. As Mars becomes more explored, it becomes a more quotidian setting that no longer captures the imagination," Sheehan told LiveScience in August.

That hasn't kept excitable space-lovers from clinging to their own myths about Mars. In 1976, for example, NASA's Viking 1 spacecraft snapped a picture that seemed to show a massive humanoid face on the planet's surface. Scientists pointed out that the image was a trick of light and shadow, but UFO lovers paid them little mind. (In 1998 and 2001, photos snapped by NASA's Mars Global Surveyor revealed the "face" to be an ordinary butte.)

The Curiosity mission, which landed a car-size rover equipped with 165 pounds (75 kilograms) of scientific equipment on the Red Planet, may have injected some of the excitement back into public discussions of Mars. The rover's NASA-run Twitter feed, for example, has more than 1.2 million followers.

Grotzinger and other Curiosity scientists will hold a press conference Monday (Dec. 3) at the fall meeting of the American Geophysical Union (AGU), though NASA officials say there will be no major announcement, only an update of the rover's soil analysis.

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